Doctors of Optometry Course Notes

Transcription

1 Doctors of Optometry Course Notes OD25 2 CE Scleral Lenses Basic Fitting to Advanced Problem-Solving Monday, February 19, :45 pm 5:45 pm Georgia A/B 2 nd Fl Presenter: Dr. Maria Walker Dr. Maria K. Walker earned her Doctor of Optometry and Master of Vision Science degrees from The New England College of Optometry. She then completed a residency in Cornea & Contact Lenses at Pacific University. Dr. Walker currently teaches at the University of Houston College of Optometry, and is pursuing her PhD in scleral lenses. Her main interests include contact lens optics, corneal physiology, scleral contact lenses, and multifocal lens performance. Course Description This 2-hour course provides a comprehensive discussion of fitting and evaluation of scleral contact lenses. It starts with basic description of the various lenses, designs, and overall fitting philosophy then progressing through every step of the fitting process. It will cover fitting for various conditions with both full scleral lenses and mini-scleral lenses. The course includes patient selection, pre-fitting diagnostic evaluation of the patient, specialized testing, initial diagnostic lens selection and evaluation, lens ordering, follow-up care, modification of the fit, problem-solving, specific care and handling of lenses and in-office management tips. The course is appropriate for those who have little to no experience with scleral lens fitting but, for those who have scleral experience, will also cover more advanced tips for solving the complex fitting challenges that sclerals can present. 1

2 Doctors of Optometry Course Notes NOTES: 2

3 Scleral Lenses: Basic Fitting to Advanced Problem Solving Maria K Walker, OD, MS, FAAO, FSLS BC Doctors of Optometry, Annual Conference 2018 Intro to Scleral Lenses (SGP) Scleral lens indications Scleral lens nomenclature Fitting concepts for SGPs Scleral lens application, removal, handling Scleral lens fitting and management Complications with sclerals Scleral Lens Indications 1. Irregular astigmatism!!keratoconus / Pellucid Marginal Deg.!!Post Corneal Transplant!!Post Radial Keratectomy (RK) Post RK!!Post LASIK/PRK &'&%!!Post Intacs!!Corneal Scarring 2. Ocular surface protection!!post surgical!!ocular surface disease (OSD) Keratoconus 3. Other!!High Rx, amblyopia, myopia control, prosthetics, aphakia, and more ()*+,-%./01234+,5*6% Post Transplant!"#$%&#% Tear Film Reservoir '()(*+"#$%&#, -$)+,(+,./,01,233,#&%4$%,05&),6789! 7428*%&9+*24+% 7*06%,6%82*4:*2%:;40%<33%+428*2%:;40% =>?@! Scleral Lens -$)+,:$&%+, $);%$#<,1),05$, +"#$%&%!13$=5&0, #(3(0$>,0$&%, %$+$%?1(%, "&/&"(0<%.+316:% A0+,3,:*-%:*42% 2*6*2B1,2% 94C49,:)% Photo Credit: Boston Sight Optic Zone (OZ): Scleral Lens Zones The central zone of the lens Transition Zone (TZR): Peripheral to the OZ, between OZ and limbal zone Intermediate Zone (IZR): Peripheral to TZR, positioned over the limbus Landing Zone (LZR): Begins where the lens lands on the conjunctival tissue Scleral Lens Terminology Overall Diameter (OAD): longest diameter of lens Total Sagittal Depth: height of the lens from base to apex Base Curve (BC): curvature of the optic zone #%

4 Sagittal Depth: Vault of the Lens Understanding Scleral Images Diameter dependent Base curve dependent Small Diameter = Shallow SAG Large Diameter = Deep SAG White light Cobalt Blue with NaFl Steep BC = Deep SAG Flat BC = Shallow SAG OCT image of lens on eye Optic Zone (OZ) Transition Zone (TZR) Intermediate Zone (ITZ) Landing Zone (LZR) Scleral Lens Fitting Optic Zone (OZ): Fitting the Zones Vault Transition Zone (TZR): Vault Intermediate Zone (IZR): Vault Landing Zone (LZR): Land evenly and smoothly Fitting Technique: Fluorescein Fitting Technique: Fluorescein!%

5 Ferris State Scleral Lens Fit Scale Tear Reservoir Layer 125um 475um It is Not Always Reasonable to Expect a Uniform Tear Reservoir Layer % Optic and Transition Zones: Vault Scleral Lenses will Settle over time 100um Expect microns lens settling 200um 400um Patrick Caroline Apical Bearing 8)0$%3$>(&0$,@1)$,A-(3:&#B, Appropriate Limbal Clearance Too o much Inadequate Limbal Clearance Ideal Clearance: ~200um D%

6 (Scleral) Landing Zone Ideal Scleral Alignment Well-aligned Scleral Landing No blanching of blood vessels No impingement No edge lift Photo credit: Greg DeNaeyer, OD Avoid Scleral Bearing Summary of Fitting Goals Blanching Impingement Optic/central and Transition zone: vault 200um after settling Intermediate Zone: vault 40-70um clearance Landing Zone: landing Soft and wide landing Minimal movement Monitor for corneal edema Scleral Lens Application Tools Scleral Lens Application E%

7 Application Application Bubble Step 1 Step 2 Step 3 Application Considerations Removal!! Dexterity (Parkinsons/tremors)!! Eyelid apertures!! Visual Status!"#$%##&'##($)#(*$+(*#',#'$ Problems with Removal? Almost always associated with technique RARELY because of fit or patient anatomy Patient Education is KEY F%

8 Rigid Lens Cleaning Products Cleaning Products Scleral Lens Application Solution MUST be preservative free Sterile saline: most common solution Vials: ScleralFil (B&L) Lacripure (Menicon) Addipack (generic) Super cleaners / Polishes Safe in the eyes Bottles: Purilens (generic) Alternative Application Solutions Preservative Toxicity Preservative free artificial tears Autologous Serum severe OSD G*B,*H%1I%JC:13*:2)% Always use preservative free application solutions SGP Management SGP Baseline Testing Visit 1: Baseline testing and Diagnostic fitting Visit 2: Lens dispense and training Visit 3 (1 week): Initial follow-up Visit 4 (1 month): Secondary follow-up Visit 5 (6-12 months): Long-term follow-up Vision, medications, history Scarring, overall health of cornea Corneal pachymetry (global) Eyelid health Intraocular pressure <%

9 Baseline Data to Monitor Corneal Changes Corneal Scarring -! Corneal Pachymetry (global) -! OCT -! Pentacam -! Endothelial Cell Density -! Corneal Staining -! Neovascularization -! Corneal Scarring -! Watch out for -! Neo -! Microsystic edema -! Endothelial blebs, poly/pleo-morphisms Corneal Staining Follow-Up Examinations Pre-lens removal: Fit and vision Beginning of day vision and comfort End of day vision and comfort Evaluate tear exchange Post-lens removal: Monitor for corneal edema (pachymetry) IOP Corneal staining, scarring GPC, overall health check Evaluating Tear Exchange Instill fluorescein over the top of the lens and observe movement L10,:12,08%M120*4+%M;408*6N% O;,9P0*66% C$D1%$,!"E-, FG$%,9(+/$)+$, 9(H$%$)"$,'&/, Photo Credit: Pam Satjawatcharaphong, OD ED% K%

10 Signs of Corneal Hypoxia Epithelial Bogging Q*1B469A+42,U4510% L,9219)659%(-*34% Q,R10%*:S4+S%!T#K% Eyelid Health Scleral Lens Complications Handling Complications Application bubble Removal difficulties Surface non-wetting Poor patient education Fit Complications Apical and/or limbal bearing Conjunctival impingement or edge lift Impression rings Uneven landing zones Loose lens syndrome Tight lens syndrome Application Bubble Application Pearls CLEAN and DRY hands Grasp the eyelids at the lash margin Head parallel to ground and lens level during application Dimple Veiling% Patient education is essential! $%

11 Application Considerations Dexterity (Parkinsons/tremors) Eyelid apertures Visual Status Lens is stuck on my eye! Attempt different peripheral locations Apply pressure to adjacent scleral tissue to break suction Slide edge of plunger underneath lens and sclera!"#$%##&'##($)#(*$+(*#',#'$ Removal Pearls Proper placement of plunger is key Removal Wet the tip of the plunger for greater suction Slow and steady wins the race Surface Non-Wetting!.%D&"$,I1)*J$K)4, V%

12 !.%D&"$,9$/1+(0+, Surface Non-Wetting/Deposits Rigid Lens Cleaning Products Boston Menicon Optimum Polishes Surface Treatment: Plasma Plasma Treatments! NOT a true coating! Improves (initial) surface wettability A finished lens is bombarded with high-energy radio waves in an oxygen-rich environment (Kurtis Brown, Menicon) Oxygen radicals dislodge hydrocarbons (oils) and rearrange surface molecules! carbon migrates away and nitrogen migrates towards lens Ionizes the surface of the lens (attractive to liquids) Result: wettable lens surface Surface Treatment: HydraPEG -! A true coating! -! Covalently bound to the surface of the lens (after plasma treatment) -! Polyethylene glycol based coating to improve lubricity and increase comfort and wearability of a rigid lens -! Available on corneal, scleral, hybrid, and soft contact lenses Surface Treatment: HydraPEG 90% water PEG-based polymer covalently (permanently) bonded to CL #T%

13 Polyethylene Glycol (PEG) Tangible HydraPEG Separates the lens material from the tear film Optically-clear coating encapsulates the core contact lens with a mucin-like hydrophilic shell. Properties of PEG: Lubricious, viscous, dependent on the length of the polymer and treatment of the surface Apical Bearing Ideal Clearance: ~200um Epithelial breakdown Limbal Bearing E1%)$&#,L%1+(1), Epithelial breakdown Punctate Staining!.:$/(05$#(&#,M:%1+(+,%$#&0$>,01,4%&G,$"0&+(&% CN,!$?$%()+O<,$0,&#,PQRS% ##%

14 7(WO%(X(N%?QW(G?JG% 7?LYZ&% Avoid Scleral Blanching Impingement <$% Excess Scleral Lift Uneven Scleral Bearing Shadow Conjunctival Misalignment Toric Scleral Design "!Conjunctiva / Sclera is toric in nature "!Non-symmetrical surface "!Nasal side is flatter and higher "!Temporal side is steeper but lower Scleral Elevation Map #!%

15 Conjunctival Impression Rings & Staining T()4.$".#&,83/()4$3$)0, 83/%$++(1),U()4, Scleral Lens Complications Management complications (acute) Lens awareness Corneal edema Surface non-wetting, sensitivities to solutions Lens bearing, over-settling Management complications (chronic) Apical and/or limbal bearing Corneal edema / bullous keratopathy Corneal epitheliopathy, infiltrates Corneal neovascularization Conjunctival prolapse Tear film fogging Lens deposits, scratches Inflammation, infection Monitor Corneal Swelling Pentacam or handheld pachymeter Baseline readings are key 34 um central swelling 5.2% Corneal Edema with Sclerals?!" &'" #%" $" &'" #%" #" #%" &'" 1.! Michaud L, van der Worp E, Brazeau D, Warde R, Giasson CJ. Predicting esti-mates of oxygen transmissibility for scleral lenses. Contact Lens Ant Eye2012;35: ! Jaynes JM, Edrington TB, Weissman BA. Predicting scleral GP lens entrappedtear layer oxygen tensions. Contact Lens Ant Eye 2015;38: ! Compãn V, Oliveira C, Aguilella-Arzo M, Molla S, Peixoto-de-Matos SC,Gonzales-Meijome JM. Oxygen diffusion and edema with modern scleral rigid gas permeable contact lenses. Investig Ophthalmol Vis Sci 2014;55: yo Newly Dx KC: Right Eye 19yo hispanic male Dx with KC 4 years ago CXL OU in early 2017 Scleral lens wearer since 2016 No complaints with scleral lens wear, 16h per day! Occasional blur OS after several hours of wear (when probed) #D%

16 E1%)$&#,L>$3&, Post Transplant T%$*!VT+, 9(H$%$)"$,'&/, T1+0*!VT+, White female 56yo PKP 2 years ago OD LKP 1 year ago OS still no lenses Scleral lenses OD since 2016 No visual complaints or issues with sclerals Epithelial Bogging QWXPSXR2, RQXQYXR2, 9(H$%$)"$,'&/, Epithelial Bogging E1%)$&#,L/(05$#(1/&05<,!! Cause unknown!! Non-nutritious saline beneath lens!! Potential etiologies:!!loss of glycocalyx layer!!epithelial edema!!osmotic imbalance!! Patients asymptomatic!! Does not appear to be long-term effect CN,!$?$%()+O<,$0,&#,PQRS% Treatment: Change application solution Change fit to decrease vault Educate patients taking medicated drops Educate patients on proper use of solutions Patient education is the key to ScCL success #E%

17 What is in the Tear Fluid Reservoir (TFR)? Baseline OCT Midday Fogging 4h post application Mucous Components Aqueous Components Proteins Lipids alterations in many anterior surface diseases 8h post application Application Solution Natural Tear Film Tear Fluid Reservoir Managing the Fog Alter lens design to decrease excess clearance Managing the Fog Alter lens design to decrease excess clearance Managing the Fog Conjunctival Prolapse High viscosity application solution Prolapse Recessed Prolapse #F%

18 Conjunctival Prolapse Axial Map Elevation Map Inferiorly decentered lens Conjunctival Prolapse Conjunctival Prolapse Inflammatory Response Cause: Negative pressure forces beneath the lens low-lying cornea Effect: Potential neovascularization and limited nutrient availability to limbal cornea Management: Adjust peripheral lens fit Monitor if mild (<3 clock hours)!!allergies!!solution sensitivity!!poor fitting lens!!surface debris toxicity!!infection!!material sensitivity (rare) Inflammatory Response '&0%(Z,'$0&##1/%10$()&+$,[,\,A''T*\B, '$&+.%()4,8)]&33&;1),, C%$&O+,>1=),"13/1)$)0+,1D,05$,$Z0%&"$##.#&%,3&0%(Z, &)>,^1).#&,1""#.>$)+,AU&_&+5$O5&%,$0,&#N,LZ/,L<$,U$+,PQRSB, ''T*\,#$?$#+,.+$>,"#()("&##<,01,>(&4)1+$,9%<,L<$, L#$?&0$>,(),`E,!, ,01,"1)0%(:.0$,01,$;1#14<a,, Allergic response! remove allergen! consider steroid pulse Material / Solution Sensitivity! Change accordingly 8)]&33&9%<, #<%

19 2/2/18 Infection: Microbial Keratitis Author (year) SGP Indica;on(s) Infec;ous Organism(s) Taking Taking steroids (y/ an;bio;cs (y/ n) n) Comments Severinsky et.al. (2014) post- PK Not cultured Unknown Unknown poor compliance Severinsky et.al. (2014) post- PK Not cultured Unknown Unknown poor compliance Fernandes et.al. (2013) OCP & SS Staph., Corynebact., & Microsporidia Farhat & Sutphin 29 (2014) GVHD Acanthamoeba Y Y Zimmerman & Marks 8 (2014) Neurotrophic Unable to determine on kera55s 2^ HSK culture Y N epi defect N Y poor compliance Microbial Keratitis Author (year) SGP Indica;on(s) Infec;ous Organism(s) Taking Taking AB (y/ Comments steroids (y/n) n) Rosenthal et.al. (2000) PED post- PK Mycobacterium abcessus Y Y epi defect Rosenthal et.al (2000) PED post- PK Streptococcus pneumonia Y Y Rosenthal et.al. (2000) PED post- PK Strep & Staph Y Y epi defect Rosenthal et.al. (2000) PED post- PK Staphylococcus epidermidis Y Y epi defect Kalwerisky et.al.(2012) Kalwerisky et.al.(2012) Exposure keratopathy Exposure keratopathy MRSA N Y Pseudomonas aeruginosa N Y Major Risk Factors: Ocular surface disease (Epithelial compromise) Steroid use Australian MK Incidence Study Incidence per 10,000 Over Night Wear* 19.5 Additional Unknown Complications Epithelial and Endothelial long-term Health Occasional* Over Night Wear Daily Disposable* 2 10 Long term effects of Conjunctival Compression Daily Wear* 1.7 Long term Limbal Health Implications RGP * Hydrogel lens materials only (silicone hydrogels not included) Dart J., Epidemiology of MK Have Silicone Hydrogels Had Any Impact? Paper presented at British Contact Lens Association Clinical Conference, June 2007 from The incidence of contact lens related microbial keratitis in Australia. Stapleton F, Keay L, Edwards K, Naduvilath T, Dart J, Brian G, Holden B in submission.?? mk_walker@central.uh.edu Looking ahead Scleral Lenses currently indicated for irregular corneas Ongoing research will help us learn about the acute and physiological effects of these lenses Caution should be taken when fitting normal corneas Thank you! Please feel free to me with any questions: mkwalker@central.uh.edu 17